I built a tactical rifle on a Savage 10 action using a aftermarket barrel, trigger, and stock. I set my headspace carefully, loaded a few primed cases and test fired with the action out of the stock. All the primers went pop, bolt closure was normal and figured I was good to go. Took it to the range loaded my first round and it clicked but no bang. No mark at all on the primer. Tried a few more rounds with no luck. Talked to several club member one of whom is a pretty accomplished gunsmith and could come up with no reason why it should not fire.
Brought it home, tried a few primed cases with no bullet or powder with the gun in the stock no luck, took the action from the stock reset the headspace and all went pop. Put it back in the stock, no pop. I removed the front action screw and took .125 off it retightened it and the pop came back.
Told my gunsmith buddy and he just scratched his head, 1000 rounds later still don't know why that .125 inch on that screw kept the firing pin from hitting the primer.
file a 1/16 of a inch off the offending screw and see if that cures it is my advice
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